void
setup( void )
{
  P1DIR = 0b10010001;  // Port 1 pins 7, 4, and 0 are outputs
  P1OUT = 0b10010000;  // enable the H-bridge using pin 4
                       // and begin with pin 7 high and 1 low
  //P1OUT = 0;
}

void
loop( void )
{
  P1OUT ^= 0b10000001; // toggle pins 7 and 0 to reverse motor
  delay( 2000 );       // each direction for 2 seconds 
}